Particle system:
A modeling technique to enable the rendering of explosions, and other complex physical phenomena such as fire, smoke, snow, clouds, rain, dust, or wind.

Patch:
A small program to add on to an existing piece of software, with the purpose of improving (e.g. integrating 3D functions) or correcting (e.g. removing bugs) its performance.

PCB (Printed Circuit Board):
A fiberglass board on which chips and other components are connected via copper pathways. For example, your 3D Prophet graphics board is a PCB.

PCI (Peripheral Connect Interface):
The expansion bus slots found at the back of most PCs. Network cards, audio and graphics boards, and hard disk controllers are the different peripherals using the PCI bus. The PCI bus transfers information to and from the peripheral and the operating system.

Perspective correction:
This is the modification of textures while taking into account convergence when moving away from an object, which removes distortion that appears when a texture map is applied to a polygon in space. This function measures the depth of the scene while rendering texels onto the surface of polygons, creating the illusion that objects nearer the forefront of the screen are larger, whilst allowing parallel lines to converge in the distance.

Pipelining:
AGP graphics boards can queue multiple commands, which means that during the memory/bus access time of one command other commands are being issued.

Pixel:
Abbreviation for PIcture ELement. This is the smallest element that can be assigned to a specific color, i.e. the "dots" that make up your TV or computer screen pictures. It is the intersection of a column and a line on a screen: in an 800 by 600 resolution (800 columns by 600 lines), there are 800x600 pixels = 480,000.

Pixelisation:
A problem caused by the inability of some graphics boards to display changes in pixel appearance when the picture is zoomed, due to the slow frame rate of some devices. 3D Prophet graphics boards correct this problem by applying a texture to an object and then regularly updating the state of the texture and the pixels of which it is comprised, processing by bilinear filtering or mip-mapping. This is updated frame by frame as opposed to being updated only when necessary.

Polygon:
A three or more sided 2D shape. These are used to create 3D environments.

Primitive shapes:
Simple shapes assembled to create the final shape of one object (sphere, cube, cone, cylinder etc.)